This list includes the singles that reached the number one place on that chart in 2015.
The preceding conversation:
See the 2 person dialog:
 - What was the best-selling single of 2015?.
 - List of Oricon number-one singles of 2015 The highest-selling singles in Japan are ranked in the weekly Oricon Singles Chart, which is published by "Oricon Style" magazine..
 - What factors affect the ranking?.
 - The data are compiled by Oricon based on each singles' weekly physical sales..
 - Any other interesting information?.
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